Corrugated tube-mounting structure

ABSTRACT

A corrugated tube includes a tubular body, formed with a slit extending in an axial direction of the tubular body; a plurality of ridge portions, formed on an outer periphery of the tubular body and arranged side by side in the axial direction; and a lap portion, protruded from one of opposed end portions of the tubular body which are separated by the slit and extended toward an inner face of the other opposed end portion of the tubular body. A plurality of fixation members are provided on the outer periphery of the tubular body to fix the corrugated tube onto the panel body in a state that the tubular body is so twisted that the slit is spirally extended.

BACKGROUND OF THE INVENTION

This invention relates to a structure of mounting a corrugated tube forfitting on a wire harness or the like, and more particularly to astructure of mounting a corrugated tube of the overlapping type in whicha lap portion, formed in a projected manner at one of opposed side edgesof a slit formed in the corrugated tube in an axial direction thereof,is laid on an inner face of the other side edge portion.

Generally, in a corrugated tube used for bundling and protectingelectric wires for an electronic equipment, a wire harness for a vehicleor others, spiral or annular ridge portions are formed continuously onan outer peripheral face of a resin tube to form a bellows-likeconstruction, thereby imparting flexibility to the corrugated tube.

In order that a wire harness or the like can be easily inserted into andremoved from the corrugated tube for protecting the wire harness, a slitis formed in the corrugated tube, and extends in the axial directionthereof.

However, when such a corrugated tube is bent along an installation path,the slit is partially opened in the vicinity of a central portion of thebent portion, and the inserted wire harness or the like projectsoutwardly through the opened portion of the slit, thus adverselyaffecting the inserting operation, and besides there is a probabilitythat the wire harness is caught by the opposed side edges of the slit,so that an insulating sheath of the wire harness is damaged. Therefore,usually, an adhesive tape is wound on the outer peripheral face of thecorrugated tube, thereby preventing the slit from being opened. However,there has been encountered a problem that this taping operation requiresmuch time and labor.

In order to solve the above problems with the corrugated tube, therehave been proposed various corrugated tubes of the overlapping type inwhich a slit will not be opened to form an opened portion even when thecorrugated tube is bent.

A corrugated tube 1 of the overlapping type, shown in FIGS. 9 and 10,comprises a tubular body 3 of an integrally-molded construction whichincludes a base plate 7 and a bellows-like portion 9 having a series ofarcuate ridge portions 10 which are formed in a bulged manner on anouter peripheral face of the tubular body except the base plate 7, andare arranged side by side in the axial direction of the tubular body 3.

A straight slit is formed in the base plate 7 in the axial direction ofthe tubular body 3, so that a strip-like lap portion 8 is formed at oneof opposed side edges of this slit in a projected manner. Thereafter,the tubular body 3 is formed by heat into such a shape that the lapportion 8 is laid on (laps on) the inner face of the other side edgeportion of the slit, thereby forming the corrugated tube 1 of theoverlapping type as shown in FIGS. 9 and 10.

In the corrugated tube 1, the lap portion 8, laid on the inner face ofthe other side edge portion of the slit, has a strip-like shape, and hasa distal end edge extending straight in the axial direction.

Therefore, when inserting a wire harness W into the corrugated tubeafter expanding the slit, the wire harness W is less liable to be caughtby the distal end edge of the lap portion 8, and the harness-insertingoperation can be effected smoothly. And besides, there is no probabilitythat the distal end edge of the lap portion 8, laid on the innerperipheral face of the corrugated tube 1, damages an insulating sheathof the inserted wire harness W.

As shown in FIG. 11, the corrugated tube 1 is fixed to a predeterminedportion of the wire harness W by adhesive tapes T or the like woundrespectively on opposite end portions of the corrugated tube, as shownin FIG. 11.

In this case, the corrugated tube 1 is so arranged that the wire harnessW will not be exposed to an external view even when the corrugated tubeis bent, and it is not necessary to wind the adhesive tape T on theouter peripheral face of the corrugated tube 1 over an entire areathereof.

As shown in FIG. 12, the corrugated tube 1, together with the wireharness W, is fixed to a vehicle body panel 15 of a vehicle, forexample, by inserting clip portions 17 a of band clips 17 (fastened onthe outer peripheral face of the corrugated tube 1) respectively intomounting holes 16 in the vehicle body panel 15.

When installing the wire harness W, protected by the corrugated tube 1,on the vehicle body panel 15 or the like, the corrugated tube need to bebent along an installation path, as shown in FIG. 12.

In the above corrugated tube 1, however, the lap portion 8 is formedinto a strip-like shape, and besides end walls 12 and 14 are formedrespectively at peripheral ends of each ridge portion 10 opposed to eachother with the slit lying therebetween.

Therefore, when bending the corrugated tube 1 along the installationpath, the corrugated tube 1 itself can not be easily bent, and thereforethere has been encountered a problem that the installation operation canbe adversely affected.

Particularly when the corrugated tube 1 is bent in such a manner thatthe lap portion 8 is curved inwardly as shown in FIG. 12, the end walls12 and 14 (which are parallel to the bending direction, and have highrigidity), exhibit high resiliency, and therefore the flexibility of thecorrugated tube is not good. When this corrugated tube 1 is forciblybent substantially, there are probabilities that the slit is opened inthe vicinity of a central portion of the bent portion and that one ofthe opposed side edges of the slit is broken.

SUMMARY OF THE INVENTION

It is therefore an object of this invention to provide a corrugatedtube-mounting structure in which a corrugated tube of the overlappingtype can be easily bent along an installation path.

In order to achieve the above object, according to the presentinvention, there is provided a method of mounting a corrugated tube ontoa panel body, comprising the steps of:

-   -   providing a corrugated tube, including:        -   a tubular body, formed with a slit extending in an axial            direction of the tubular body;        -   a plurality of ridge portions, formed on an outer periphery            of the tubular body and arranged side by side in the axial            direction; and        -   a lap portion, protruded from one of opposed end portions of            the tubular body which are separated by the slit and            extended toward an inner face of the other opposed end            portion of the tubular body;    -   providing fixation members on the outer periphery of the tubular        body;    -   twisting the tubular body such that the slit is spirally        extended;    -   bending the twisted tubular body; and    -   attaching the fixation members onto the panel body while the        corrugated tube is bent.

In this method, those portions of the tubular body, disposed near to thelap portion, can disperse a bending stress, produced upon bending of thetubular body, in the axial direction and the peripheral direction overthe outer peripheral face to relieve this bending stress, and thereforethe corrugated tube can be easily bent along the installation pathalthough the corrugated tube has the strip-like lap portion.

Preferably, the mounting method further comprising a step of fixing thetwisted tubular body with electric wires inserted into the tubular body,before the bending step.

In this case, the tubular body is beforehand fixed to the electricwires, in such a manner that the tubular body is twisted about the axisthereof, and therefore when the tubular body, together with the electricwires, is to be installed on and fixed to the mounting portion, thecorrugated tube can be easily bent in a desired direction.

Therefore, the operator can easily bend the corrugated tube inaccordance with the installation path.

Preferably, each fixation member includes a clip member fixed on thepanel body. Here, the respective clip members are oriented to differentcircumferential directions with respect to the tubular body, when thefixation members are provided. Then the tubular body is so twisted thatthe respective clip members are oriented to an identical circumferentialdirection.

In this case, when the corrugated tube is installed on and fixed to themounting portion, the clip portions of the plurality of fixation membersare fixed respectively to predetermined portions of the mountingportion, and by doing so, the tubular body, installed on the mountingportion, is twisted about the axis thereof.

When the tubular body is fixed with the electric wires passingtherethrough, in such a manner that the slit of the tubular body isstill straight with respect to the electric wires as well as the casewith the related-art construction. Therefore the operation for fixingthe tubular body to the electric wires can be effected easily.

According to the present invention, there is also provided a structurecomprising:

-   -   a panel body;    -   a corrugated tube, including:        -   a tubular body, formed with a slit extending in an axial            direction of the tubular body;        -   a plurality of ridge portions, formed on an outer periphery            of the tubular body and arranged side by side in the axial            direction; and        -   a lap portion, protruded from one of opposed end portions of            the tubular body which are separated by the slit and            extended toward an inner face of the other opposed end            portion of the tubular body; and    -   a plurality of fixation members, provided on the outer periphery        of the tubular body to fix the corrugated tube onto the panel        body in a state that the tubular body is so twisted that the        slit is spirally extended.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and advantages of the present invention will becomemore apparent by describing in detail preferred exemplary embodimentsthereof with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a corrugated tube-mounting structureaccording to a first embodiment of the present invention, showing acorrugated tube in a straight condition before it is mounted;

FIG. 2 is a perspective view of the corrugated tube-mounting structureof FIG. 1, showing the corrugated tube in a bent condition before it ismounted;

FIG. 3 is a perspective view of a corrugated tube-mounting structureaccording to a second embodiment of the invention, showing a corrugatedtube in a straight condition before it is mounted;

FIG. 4 is a perspective view of one band clip shown in FIG. 3;

FIG. 5 is a perspective view of the other band clip shown in FIG. 3;

FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 3;

FIG. 7 is a cross-sectional view taken along the line VII-VII of FIG. 3;

FIG. 8 is a perspective view of the corrugated tube-mounting structureof FIG. 3, showing the corrugated tube in a bent condition before it ismounted;

FIG. 9 is a fragmentary, perspective view showing a corrugated tube ofthe overlapping type.

FIG. 10 is an enlarged, transverse cross-sectional view of an essentialportion of the corrugated tube of FIG. 9;

FIG. 11 is a perspective view explanatory of a related-art corrugatedtube-mounting structure, showing a corrugated tube in a straightcondition before it is mounted; and

FIG. 12 is a perspective view explanatory of the related-art corrugatedtube-mounting structure, showing the corrugated tube in a bent conditionbefore it is mounted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of a corrugated tube-mounting structure of thepresent invention will now be described in detail with reference to theaccompanying drawings. However, a corrugated tube itself in thisembodiment is similar in construction to the corrugated tube 1 of theoverlapping type shown in FIGS. 9 and 10, and therefore correspondingportions thereof will be designated by identical reference numerals,respectively, and detailed description thereof will be omitted.

A corrugated tube 1, used in a mounting structure according to a firstembodiment, is fixed to a predetermined portion of a wire harness W byadhesive tapes T or the like wound respectively on opposite end portionsthereof, as shown in FIG. 1. At this time, a tubular body 3 isbeforehand fixed to the wire harness W, passing therethrough, in such amanner that this tubular body 3 is twisted about an axis thereofrelative to the wire harness W.

Namely, the tubular body 3 is twisted about the axis thereof, so that alap portion 8 extends spirally along an outer peripheral face of thetubular body 3. In this embodiment, although the tubular body 3 istwisted about the axis thereof through an angle of about 90 degrees,this twisting angle can be suitably changed in accordance with theoverall length of the tubular body 3 and so on.

As shown in FIG. 2, the corrugated tube 1, together with the wireharness W, is fixed to a vehicle body panel 15 of a vehicle, forexample, by inserting clip portions 17 a of band clips (clamp members)17 (fastened on the outer peripheral face of the corrugated tube 1)respectively into mounting holes 16 in the vehicle body panel 15.

At this time, the tubular body 3 is bent generally at right angles inaccordance with a path of installation of the wire harness W. However,this tubular body is installed on and fixed to the vehicle body panel 15in such a manner that the tubular body is twisted about the axisthereof, and those portions of the tubular body 3, disposed near to thelap portion extending spirally along the outer peripheral face of thetubular body 3, can disperse a bending stress, produced upon bending ofthe tubular body 3, in the axial direction and the peripheral directionover the outer peripheral face to relieve this bending stress, andtherefore the corrugated tube 1 can be easily bent.

Therefore, the operator can easily bend the corrugated tube 1 along theinstallation path though the corrugated tube has the strip-like lapportion 8, and the installation operation can be effected easily.

A corrugated tube 1, used in a mounting structure according to a secondembodiment, is fixed to a predetermined portion of a wire harness W byadhesive tapes T or the like wound respectively on opposite end portionsthereof, as shown in FIG. 3.

At this time, a tubular body 3 need only to be fixed to the wire harnessW, passing therethrough, in such a manner that the opposite end portionsof this tubular body 3 are fixed straight to the wire harness W as isthe case with the tubular body 3 of FIG. 11, and therefore the operationfor fixing the tubular body 3 to the wire harness W is easy.

Then, a pair of band clips (clamp members) 21 and 31 are fastenedrespectively on those portions of the outer peripheral face of thetubular body 3 disposed near respectively to the opposite ends of thistubular body 3.

As shown in FIG. 4, the band clip 21 is integrally molded of aninsulative resin material, and includes a winding bland 24 for beingwound on the outer peripheral face of the tubular body 3, a bandpassing/retaining portion 22, which is formed integrally at a proximalend of the winding band 24 so that a distal end portion of the windingband 24 can be passed through and retained by this bandpassing/retaining portion 22, and a clip portion 23 formed on andprojecting from an outer face of the band passing/retaining portion 22.

A series of retaining teeth 28 like rack teeth are formed on an outerperipheral face (lower face in FIG. 4) of the winding band 24, and arearranged in a direction of the length of the winding band 24 over apredetermined range (see FIG. 6).

A retaining tongue 27 for retaining engagement with the retaining teeth28 of the winding band 24 is formed within a passage hole in the bandpassing/retaining portion 22.

The retaining teeth 28 of the winding band 24 and the retaining tongue27 of the band passing/retaining portion 22 are so designed that themovement of the winding band 24 relative to the passage hole in the bandpassing/retaining portion 22 in an inserting direction is allowed, whilethe movement of the winding band 24 relative to this passage hole in awithdrawing direction is inhibited through the retaining engagementbetween the retaining teeth and the retaining tongue.

A plurality of displacement stoppers 26 of a rib-like shape are formedon the inner peripheral face (upper face in FIG. 4) of the winding band24 (which is held in contact with the outer peripheral face of thecorrugated tube 1 at the time of the clamping) at predeterminedintervals in the direction of the length of the winding band 24. Thedisplacement stoppers 26 are so shaped and sized as to be retaininglyengaged in any of outer peripheral grooves each formed between adjacentridge portions 10 of the tubular body 3. These displacement stoppers 26serve to prevent the band clip 21 from being displaced in the axialdirection relative to the tubular body 3.

A rotation stopper 25 is formed on that portion of the inner peripheralface of the winding band 24 disposed near to the band passing/retainingportion 22. As shown in FIG. 6, the rotation stopper 25 is fitted in agap between end walls 12 and 14 which are formed respectively atperipheral ends of the ridge portion 10 opposed to each other with aslit (in the tubular body 3) lying therebetween, and by doing so, theband clip 21 is prevented from being rotated in the peripheral directionrelative to the tubular body 3.

As shown in FIGS. 3 and 6, the band clip 21 is fixed to the outerperipheral face of the tubular body 3 against movement relative to thistubular body 3.

As shown in FIGS. 5 and 7, the other band clip 31 is similar inconstruction to the band clip 21 except that the position of formationof a rotation stopper 25 on an inner peripheral face of a winding band24 is different from that of the rotation stopper 25 of the band clip21, and therefore detailed description of the other band clip is omittedhere.

The clip portions 23 of the pair of band clips 21 and 31, fixedrespectively to those portions of the tubular body 3 disposed nearrespectively to the opposite ends thereof, are inserted respectivelyinto mounting holes 16 in a vehicle body panel 15, so that thecorrugated tube 1, together with the wire harness W, is fixed to apredetermined portion of the vehicle body panel 15. The band clips 21and 31 are fixed to the tubular body 3 in such a manner that their clipportions 23 face in their respective predetermined directions so thatthe tubular body 3, installed in a bent condition on the vehicle bodypanel 15, can be twisted about the axis thereof, as shown in FIG. 8.

Namely, in this second embodiment, the pair of band clips 21 and 31 arebeforehand fixed to the outer peripheral face of the tubular body 3 insuch a manner that their clip portions 23 are circumferentially spacedan angle of 90 degrees from each other about the axis of the tubularbody 3, and face in their respective predetermined directions, as shownin FIGS. 3, 6 and 7. Here, the direction of projecting of the clipportion 23 of each of the band clips 21 and 31 is determined by theposition of formation of its rotation stopper 25 fitted in the gapbetween the end walls 12 and 14 on the tubular body 3.

Therefore, when the corrugated tube 1, together with the wire harness W,is installed on and fixed to the vehicle panel 15, the clip portions 23of the pair of band clips 21 and 31, beforehand fixed to the outerperipheral face of the tubular body 3, are fixed respectively to thepredetermined portions of the vehicle body panel 15, and by doing so,the tubular body 3, installed on the vehicle body panel 15, is twistedthrough an angle of about 90 degrees about the axis thereof, as shown inFIG. 8.

At this time, the tubular body 3 is bent generally at right angles inaccordance with the installation path of the wire harness W. However,this tubular body is installed on and fixed to the vehicle body panel 15in such a manner that the tubular body is twisted about the axisthereof, and those portions of the tubular body 3, disposed near to alap portion extending spirally along the outer peripheral face of thetubular body 3, can disperse a bending stress, produced upon bending ofthe tubular body 3, in the axial direction and the peripheral directionover the outer peripheral face to relieve this bending stress, andtherefore the corrugated tube 1 can be easily bent.

Therefore, the operator can easily bend the corrugated tube 1 along theinstallation path though the corrugated tube has the strip-like lapportion 8, and the installation operation can be effected easily.

In the second embodiment, although the tubular body 3 is twisted aboutthe axis thereof through the angle of about 90 degrees, this twistingangle can be suitably changed in accordance with the overall length ofthe tubular body 3 and so on.

Namely, the pair of band clips 21 and 31 are beforehand fixed to theouter peripheral face of the tubular body 3 in such a manner that theirclip portions 23 are circumferentially spaced a desired angle from eachother about the axis of the tubular body 3, and face in their respectivepredetermined directions, and by doing so, the angle of twisting of thetubular body 3 is determined.

In the case where the tubular body 3 has such a large overall lengththat the twisting angle becomes large, the number of the band clips,beforehand fixed to the outer peripheral face of the tubular body, maybe increased, and in this case the tubular body 3 is twistedsequentially along the length thereof.

In the corrugated tube-mounting structures of the present invention, theconstructions of the ridge portions and the lap portion, theconstruction of the clamp members and so on are not limited to those ofthe above embodiments, but can take various forms within the scope ofthe invention.

For example, there can be used clamp members each including a mountingportion for being fixed to the tubular body along the length thereof byan adhesive tape or the like, and a clip portion extendingperpendicularly from this mounting portion.

1-3. (canceled)
 4. A structure comprising: a panel body; a corrugatedtube, including: a tubular body, formed with a slit extending in anaxial direction of the tubular body; a plurality of ridge portions,formed on an outer periphery of the tubular body and arranged side byside in the axial direction; and a lap portion, protruded from one ofopposed end portions of the tubular body which are separated by the slitand extended toward an inner face of the other opposed end portion ofthe tubular body; and a plurality of fixation members, provided on theouter periphery of the tubular body to fix the corrugated tube onto thepanel body in a state that the tubular body is so twisted that the slitis spirally extended.